FAQ: Can you pay with an NFC pass
The security for an NFC pass has not been designed for payment applications, so it is different to that required by the banks of payment cards. An NFC pass can, however, be used to store a loyalty card, offer, voucher, ticket, gift card or token. This might include a meal ticket, promotional gift or free drink, which has no specific value.
An NFC pass could be used to trigger an adjustment to a payment requested by your payment system, such as applying a member discount, but if there is any residual payment that would have to be made using a bank card.
Apple will always carefully consider any new proposed application of NFC passes.